Aaron Alexis

By File photo by The Associated Press

September 16, 2013 | 8:39 p.m. CDT

This booking photo provided by the Fort Worth Police Department shows Aaron Alexis, arrested in September, 2010, on suspicion of discharging a firearm in the city limits. The FBI has identified Alexis, 34, as the gunman in the Monday shootings at at the Washington Navy Yard.